1. Field of the Invention
The present invention relates to an electrical connector assembly, and particularly to a combined pick up cap and electrical connector in which the pick up cap is attached onto the electrical connector.
2. Description of the Prior Art
On many production lines, electronic components such as electrical connectors are accurately positioned on a printed circuit board (PCB) such as a motherboard by means of a vacuum suction device. Since an electrical connector typically has a multiplicity of through holes in a top portion thereof, a pick up cap has to be pre-attached on the electrical connector. The vacuum suction device is then able to engage on a flat top surface of the pick up cap, in order to reliably move and accurately position the electrical connector onto the PCB. This kind of pick up cap is shown in U.S. Pat. No. 6,413,111 to Pickles et al., dated Apr. 6, 1993.
Commonly, a Land Grid Array (LGA) socket comprises a housing mounted on a printed circuit board, a metal clip pivotably engaged on the housing, and a plurality of contacts secured in the housing. The metal clip has a window in the center. Each contact protrudes a predetermined height above a surface of the housing to contact with a Land Grid Package (LGP), and the exposed portions of the contacts are liable to be distorted or even damaged when they are impacted by a foreign object.
On a production line, the metal clip of the conventional LGA socket is rotated downwardly to a horizontal closed position. A pick up cap is then attached on the metal clip. The pick up cap provides a smooth top surface for a vacuum suction device to engage. Thus the electrical connector can be moved and accurately positioned onto a predetermined location of the PCB.
However, one problem with this type of pick up cap is that it is attached on the clip is relatively far from the exposed portions of the contacts. Foreign matter, such as wires used on the assembly line or a finger of an operator, is liable to enter a space between the metal clip and the housing. The exposed portions of the contacts are liable to be damaged and/or contaminated by such foreign matter.
In view of the above, a new electrical connector assembly with a pick up cap which overcomes the above-mentioned disadvantages is desired.